> All of the evidence for wage discrepancies between male and female is due largely to women's role of motherhood.

Citation needed. It's PART of the discrepancy, but the evidence is far from conclusive. Even the link you pasted shows otherwise. Women without children still peak at 90% of relative wages to men without children, which themselves are lower than wages of fathers (presumably because being in a stable relationship allows a working father to focus on their career with someone taking care of the home)